The use of cutter tools is a necessity for efficient installation of new or replacement non-metal pipes and tubing. While there are numerous types of cutters, ratchet style cutter tools have become well accepted by the industry and the consuming public. The ratchet style cutter tool is commonly used for ABS and PVC piping, rubber and neoprene hoses, and the like non-metal piping and tubing.
Ratchet style cutter tools are well known in the art. Early ratchet tools include the use of teeth to provide unidirectional movement of the cutting tool such as that disclosed in U.S. Pat. No. 2,697,875.
U.S. Pat. No. 5,129,158 discloses a plastic pipe cutter having a guillotine style cutting action.
A ratchet style cutter tool typically consists of a hand operated device that resembles a large scissors. The use of a ratchet mechanism permits a mechanical advantage in the cutting action by disseminating the cutting action over a series of steps cuts. For instance, U.S. Pat. Nos. 4,176,450 and 4,674,184 disclose cutting tools having a movable blade that is pivotally mounted to a support anvil. The anvil provides an area for securement of the pipe or tube effectively positioning the material from movement during the outward force caused by the pivoting motion of a cutting blade. The cutting blade is drawn into the material by a stepped advancement providing leverage efficiency through movement of the cutter blade into various cutting points with the sequential squeezing of handles.
Ratcheting type cutters reduce the hand force required in operation of cutting action. By squeezing the cutter tool handles, the operator produces only a partial cutting movement of the blade. Sequential actuations are required in order to advance the blade through the material to be cut. The use of the ratcheting type cutter tool takes mechanical advantage of the handle in relation to the cutting blade to provide a leveraged scissor type action. Ratchet teeth are arranged such that the mechanical advantage given each tooth increases the leverage point as the handles are squeezed. The ratchet teeth are sized and positioned to cause the cutting blade to travel through the material to be cut with a mechanical advantage force not possible with a one-to-one pivot operation found in a conventional scissors.
U.S. Pat. No. 6,766,581 discloses a cutter having a movable jaw that advances every time the handles of the tool is closed.
A non-ratcheting cutter is illustrated by U.S. Pat. No. 6,658,738 wherein leverage is obtained by movement of a pivot point allowing the handle to be operated at different angles to the material to be cut.
A problem with the prior art cutting tool is that cutting of the material must be made by placement of the cutting blade at a perpendicular angle to the pipe so as to provide a proper splice point for a coupling, elbow, or the like fitting that may be attached to the cut pipe. If the pipe is not cut at a perpendicular angle, valuable surface area is lost and the possibility of leaks increases. The operator must take care to position the cutting tool perpendicular to the material to be cut. In many instances it may not be possible or practical to position the tool in the perpendicular position. The position may be such that operation of the tool handle may be inhibited due to fixed objects that would be costly or not practical to move. For instance, if a plastic pipe was placed in a crawl space with the piping running along a side wall, it may not be possible to place a cutter tool perpendicular to the pipe. Similarly, a water pipe made of plastic might have broken behind shrubs wherein offset cutting operation is possible, but perpendicular placement of the cutting tool would require movement of the shrub.
U.S. Pat. No. 6,662,451 discloses a hedge shears having a pair of blades that are rotatably secured to the handles. The angular positioning of the blades allows for offset cutting angles.
U.S. Pat. No. 733,919 discloses an implement handle having an hinge pivot that allows operation of the handle at an offset angle to the cutting blades.
U.S. Pat. No. 869,949 discloses a scissors having a hinged handle to allow offset cutting, the hinge handle having apertures for securing the handles to the blades at predisposed positions.
U.S. Pat. No. 2,020,242 discloses a crimper/cutter tool having handles adjustable to the blades.
U.S. Pat. No. 894,710 discloses a garden shears having having a pair of blades that are hingedly secured to the handles. The hinge allows positioning of the handles to allow offset operation of the blades.
U.S. Pat. No. 3,596,355 discloses a shearing tool having a handles hingedly coupled to the cutting blades.
U.S. Pat. No. 5,974,670 discloses a multipurpose cutting tool having two pivoted cutter blades turned with two handles. A ratchet allows one cutter blade to move in response to a first handle movement.
U.S. Pat. No. 6,249,976 discloses a scissors that permits offset cutting by placement of a hinge between the handles and the cutting blades.
U.S. Pat. No. 5,317,806 discloses a pruning shears connected by use of a swivel joint along the end of a guide handle. The swivel joint includes a hinge pin and traction cable. The arms of the shears can be locked in any angular position of the swivel joint.
Thus, what is needed in the art is a ratchet cutting tool capable of operating at offset angles while maintaining the cutting blade in a perpendicular angle.